5.
Biologists in Alaska are counting walruses (海象) in the Arctic Ocean.The aim:to decide whether the walrus is an endangered species (物種).
In 1990,biologists counted 201,039walruses in the Arctic Ocean.Now,over 20years later,it seems there are fewer.After three years of counting,the US Fish and Wildlife Service estimates that there are only 15,164walruses in the area.But,scientists say,"They've not finished counting."
"We're still working on the final population estimate,"said Suzann.She is a wildlife biologist with the US Fish and Wildlife Service.
Endangered Species?
What's a possible reason for the lower walrus count?Brendan Cummings,a spokesperson for
the Center for Biological Diversity (多樣性),thinks many walruses are dying.He believes global warming is melting the ice in the waters between Alaska and Russia.That's the area where most walruses live.However,they can't live without ice.
But other scientists aren't so sure that the walruses are dying out.The US Fish and Wildlife Service biologist Doug Bum said,"We realized we were missing a lot of walrus groups."So the walrus count goes on.The counting hasn't been easy.Scientists sometimes have to guess the number of walruses that are underwater.
US law requires scientists to count the walruses every three years.Then,if the mammals (哺乳動物) turn out to be an endangered species,they will be counted every year.
66、What's the purpose of counting walruses in the Arctic Ocean?.C
A、To study the living habits of walruses.
B、To show the bad environment of the earth.
C、To see whether the walruses belong to the endangered animals.
D、To see whether the Arctic Ocean is suitable for people to live in.
67、What does the underlined word"estimate"mean in Chinese?B
A、創(chuàng)造
B、估算
C、分析
D、制造
68、According to the US law,scientists will count the walruses every year if they areB.
A、missing
B、endangered
C、sold out
D、under the water
69、Which of the following statements is TRUE?D
A、The counting of the walrus is easy.
B、Brendan Cummings is a biologist of the US Fish and Wildlife Service.
C、In 1990,biologists counted only 15,164walruses in the Arctic Ocean.
D、Brendan Cummings believes global Warming makes the walruses fewer.
70、What is the best title of the passage?D
A、Global Warming
B、Protect the Animals
C、Biologists'Work
D、Worry about Walruses.